Growing weed, and good weed at that, is all about giving your favourite ladies the right nutrients, in the right amounts, at the right time. With so many nutrient companies out there, claiming they have the best products, it can be confusing to choose what to feed your plants and at what stages of their growth.
In this article, we are going to discuss some of the basics of cannabis nutrients, so that you can start to better understand what will help your plants thrive and what will be detrimental to them.
Understanding Cannabis Nutrient Needs
Before we dive into the world of nutrients, it is important to first have an understanding of nutrient requirements in different mediums. If you are using organic soil, there is going to be enough naturally occurring nutrients to get your plant from seed to harvest with pretty damn good results. Of course, you can still look to add even more nutrients, but it is important to be careful not to overdo it and cause nutrient burn.
On the other hand, if you are growing hydroponics or in coco coir, you will need to add your own nutrients from day one in order for your plant to survive, thrive, and become the best version of itself.
Another thing to keep an eye on, for both organic soils and hydro set-ups, is the pH level of your water. For hydro, you want a pH level between 5.8-6.2, so go out and buy yourself a pH level tester and make sure you are keeping an eye on it. It isn’t as vital to constantly monitor the pH of the water you give to soil grown plants, but it can make a pretty big difference come harvest time. Soil grown weed plants love a pH of 6.0 to 7.0.
With organic soil grows, if you notice nutrient deficiencies, you can just use a veg booster or flowering booster to help improve the quality of your soil.
All the nutrients that your weed plant needs to thrive are naturally available in the environment, however, you will need to give your plants fertilizer-concentrated nutrients if you want the end product to be as potent and pure as you hope.
Here, we will focus on the needs of hydroponic (or coco-coir) growers and help you guys understand what your plants need.
Macronutrients
In order for your weed plant to grow strong and healthy, they require three specific nutrients in large quantities. These nutrients are:
- Nitrogen: This is a crucial nutrient and plays a big role in the vegetative stage.
- Phosphorous: Plays a big part in the development of your plant’s roots and during the flowering stage.
- Potassium: Is needed for overall plant health and helps to improve weed plant’s disease resistance.
These three nutrients will often be front and center of nutrient products, written as NPK ratio. The higher the numbers for each of the nutrients, the higher their concentration levels in that nutrient pack.
Other than the three nutrients mentioned above, cannabis also requires what we refer to as secondary nutrients.
- Calcium: Helps to reduce soil salinity and is crucial for cell wall development.
- Magnesium: This plays a key role in photosynthesis and the metabolism of carbohydrates.
- Sulfur: Needed for the formation of chlorophyll. It also helps the plant produce proteins, amino acids, enzymes and vitamins.
Micronutrients
As well as these important macronutrients, in order to get a truly high-quality yield, you will need to add a bunch of other micronutrients, in smaller quantities, to your soil. These include boron, chlorine, copper, manganese, molybdenum and zinc.
Dont worry, all good nutrient packs will include all of these micronutrients, so you don’t need to worry about buying them separately.
How Do I Choose the Best Fertilizer For My Plants?
Different fertilizer brands use different ratios of nutrients that they find optimal. Not only do you need to choose the fertilizer brand itself, you also need to choose whether you want to use a liquid solution, granular, or slow-release. Most growers use liquid solutions, so if you are a beginner grower, we would recommend starting off with that.
Fertilizer companies also use different ingredients in their mixtures, which range from highly chemical to natural. One final thing to look out for are supplements. Some products contain low NPK ratios and instead use nutrients that are meant to boost certain specialized aspects of the grow.
We would recommend not overcomplicating things. Stick to a normal NPK ratio and make sure your plant is getting all the macronutrients it needs. If you go overboard with chemicals, you can harm your plant, which will result in lower yields and lower quality.
After you have wrapped your head around how best to use the core nutrients, then you can feel free to move to a more complex feeding schedule.
Cannabis Nutrient Requirements For Different Stages
During the different stages of the growing process, your plant will need different types and different amounts of nutrients.
Nutrients for Weed Seedlings
During the seedling stage, your plant gets all the nutrients that it requires to survive from its seed, while it absorbs water through its leaves as the root system starts to develop and become stronger.
You actually do not need to give your plant any extra nutrients during the seedling stage, at least for the first few days anyway – instead just make sure you are keeping the plant safe from external factors and making sure it gets sufficient water. Adding additional nutrients will start during the vegetative stage.
Nutrients for Vegetative Stage
Once your plant enters the vegetative stage, this is when you need to bump up the nutrients and start playing around with the NPK ratio. Most growers will start with a low dose at a ratio of 2:1:2 at the very start of the veg stage. This is to basically introduce your plant to the nutrients and avoid nutrient burn while your cannabis plant is still pretty fragile.
Once you reach the mid-veg stage (around 6 weeks after germination), you will want to drastically increase the nutrients, which will help them develop strong and healthy foliage. At this point of the grow, you will want your ratio to be around 10:5:7. With this increase in nitrogen, you will see your plants develop luscious green foliage, as well as a heap of bud sites to be ready for the flowering stage.
During the final week of the veg stage, you will want to reduce your nitrogen levels to prepare your plants for their bloom booster. Most growers opt for a 7:7:7 ratio at this point.
Nutrients for Flowering Stage
To promote the growth of big, healthy, and potent buds, your plants need less nitrogen and more potassium and phosphorous. At this stage, potassium is the most important of the three nutrients from the NPK mixture.
For the first two weeks of flowering, we would recommend going for a 5:7:10 ratio. After this, it is common practice for growers to gradually dial up the nutrients, while always keeping potassium as the highest concentrate. By mid-flowering, the majority of growers will be feeding their plants an NPK nutrient ratio of 6:10:15.
In the last couple of weeks leading up to flushing, you want to start to tone down your nutrients levels. This helps get the plant ready for the flush, and will also make the flushing process a lot easier and more efficient. In the final couple of weeks, you want to be working with a nutrient ratio of 4:7:10.
Understanding a Cannabis Feeding Chart
When you buy nutrients in the form of fertilizer for your cannabis plants, most brands will provide growers with a feeding chart to go along with their product. Being able to properly comprehend and understand these charts is crucial to keeping your plants healthy and flourishing.
Typically, nutrients are applied to your plants once each week. As we have discussed earlier in this article, you will need to give your plant different types of nutrients at different concentration levels during different stages of the grow. In order to know what to give your plant and when, you can consult your feeding chart.
The weeks of the cycle will usually be on the x-axis of the chart, with the type of nutrients and its concentration levels on the y-axis. As well as the nutrient type and its ratio, most brands will also provide you with a feed to water ratio, which can be super useful in helping you stick to the correct feeding schedule.
Should I Use Nutrients Every time I Water?
The simple answer to this question is no. However, it is a little more complicated than that. You will need to water your plants from the seedling stage all the way to harvest. At some periods during the grow, you will need to water your plants every day, while some other points only require you to water a couple of times each week.
Don’t directly associate watering with feeding your plants nutrients. You will always need to water your plants when you feed them nutrient mix, however, it is not the other way around. You will not always need to feed them nutrients every time you water.
Preparing a Marijuana Nutrient Mix
Correctly preparing your nutrient mix can be the difference between a good harvest and a great one. The size of your yield and the quality of your buds at the end of the prow process depends entirely on how well you treat your plant as it develops. Feeding it the correct nutrients is one of the most important factors to take into account.
To properly prepare your marijuana nutrient mix, follow these simple steps.
- Prepare your water. For the best root absorption, you should get your water to around 19-21℃.
- Add your nutrients, while following all the instructions on the nutrient bottle or bag, and then stir it in until it looks properly dissolved.
- Test the EC or TDS level of your water using a PPM meter. If you need to, add more nutrients or dilute the mixture with more water until it reaches the desired level.
- Be sure to test your mixture with a pH measuring device. You might need to adjust your pH levels using a nitric or phosphoric acid pH down supplement.
- Once the concentration levels (test using a PPM measurement), pH, and temperature of your mixture are right, you can feed your plants.
Importance of PPM pH and EC
EC (electric conductivity) and PPM (parts per million) are both measurements to determine the nutrient levels in both your nutrient mixture and your grow medium. You can use a TDS (total dissolved solids) meter to test your nutrient levels. This is also a great tool to use during the flushing process, to make sure there is as little nutrients remaining in your grow medium before you start harvesting.
pH levels, as well as water temperature, are equally important metrics when it comes to determining the quality of your nutrient solution. If it is off even the slightest amount, it can significantly affect your plants’ ability to absorb nutrients. We recommend investing in a pH level tester. You can get cheap ones for around $10.00 that work perfectly fine, and will take care of your needs during the cannabis grow.
Identifying Cannabis Nutrient Issues
Overfeeding or underfeeding your plants can put them through a serious amount of stress. Remember, cannabis plants need to be taken care of and looked after properly, they are delicate and fragile beauties after all. Make sure you keep your eyes out for some of these signs of nutrient issues.
pH Imbalance
If you are not checking your pH levels properly and your water is too alkaline or too acidic, you can cause serious harm to your plants. An imbalance in pH levels can lead to nutrient lockout, nutrient deficiencies and more.
If you leave pH levels untreated, your plant size will be significantly reduced come harvest time, as well as the quality of your buds.
Nutrient Burn
This usually occurs when you over feed your plants, or when there is nutrient build up in the soil. The first signs of nutrient burn are the development of dark green leaves with neon green tips, that bend upwards at almost a 90° angle towards the ceiling.
You can treat nutrient burn by flushing your plants with pH-neutral water for at least one-week, before gradually starting to add fertilizer back into the picture.
Use a TDS meter to measure your EC and PPM levels to avoid experiencing nutrient burn.
Nutrient Lockout
Nutrient lockout is either caused by the build-up of nutrients around the root systems or by pH imbalances. The result is that your plants are unable to absorb nutrients, which leads to deficiencies.
You will notice yellow foliage, burnt leaf tips and irregular leaf shape and size, which are all good indicators of nutrient lockout. The observable symptoms can vary depending on which types of nutrients your plant is lacking.
This issue is usually treated by flushing your plants.
Overfeeding
Chemical fertilizers can very easily affect your plants if you give them too much. Some of the telltale signs of overfeeding include dry, burnt-looking leaves with yellow or brown coloring. You will also notice that the edges of the leaves will appear burnt, and they will be bent upwards.
Novice growers will usually purchase more nutrients to try and fix the problem, but will only make it worse. The only will to properly solve the issue is by doing a root flush, a pH stabilization and applying a new feeding schedule.
Nutrient Deficiency
This issue can arise from underfeeding your plants or due to nutrient lockout. The main symptoms you will see are dry foliage, yellow or brown leaves and discolored stems.
There are two ways of fixing nutrient deficiency. First is to adjust your feeding schedule and increase the amount of nutrients you are giving your plant. The other is to amend the nutrient lockout issue by flushing.
Chemical vs Organic Nutrients for Weed
Understanding the benefits of both chemical and organic nutrients will help you with your grow process a whole bunch. Both of them are good for different reasons, and should be used in different situations.
Organic nutrients are fantastic, as they are slowly absorbed into the soil and by your plants. This reduces the risk of nutrient burn and other feeding issues. Also, because it is organic, it is great for the soil, and encourages the development of a rich ecosystem of microorganisms that can help protect and grow your plant.
Organic nutrients will also not have toxic runoffs, which reduces the impact of your harvest on the environment. This makes organic fertilizers perfect for outdoor growers.
In terms of chemical fertilizers, they are great if efficiency and speed is key. They are absorbed by your plant a lot faster than organic fertilizers. Another benefit of chemical fertilizers is that they are produced with very specific ratios of nutrients, which makes it easier for you to control what your plant is consuming.
Chemical fertilizer is recommended for hydroponic photoperiod grows as well as autoflowers.
Conclusion
Wrapping your head around all the different factors that affect growing weed can be a daunting task. From light sources, to genetics, water intake and everything in between, the idea of growing your own plant might seem hard. If you are able to put the time and effort into understanding all these things, as well as understanding the nutrient requirements of your plants, you are well and truly on your way to growing some quality weed.
But remember, growing buds does not happen overnight, and you will make a few mistakes along the way. The most important thing is not to let that deter you. The more experience you get growing your own plants, the better the harvest for each one will be.